Lately I've been getting this message when attempting to save files from various programs. It seems that W7 has this default address set up and it can't find it. Sometimes I can cancel and proceed. Other times (as in the illustrated case) it simply won't let me continue. Any suggestions as to what's going on, or more particularly how can I change this default address to, say, the C drive.

The problem is not unique to the Roots Magic program. I just used it as an example. In fact, I used the free IrfanView program to open a screen capture from which I cropped the displayed error message in my first post. When I went to save that cropped picture I got the same kind of error message although in this case I selected Cancel and got the usual Save As window. It doesn't work that way with the Roots Magic error message. Clicking on cancel just brings up another error message.
There are several other programs that come up with the same message when saving something. I still think there must be some place in W7 where it is saving that peculiar address as the default.